I HAVE A Mac Intosh Mac OS X 10.4.11. I bought an Ipad , newest Ipod, and tactile mouse that I do not connect on it . I believe I must update the Mac OS . What should I do?

Indeedy.
You are several versions out of date.
The latest is Lion, details here: Apple - OS X Lion - Upgrade to Lion. Only from the Mac App Store.

Click on the apple in upper L/H corner and chose software update. Current version is OS X 10.6.8.

The version of itunes needed is not supported by OS 10.4. Is your mac a power PC on Intel based unit?

Thank you so much. My system is Intel based. How to update to latest or sufficient OS version?

By the way , when I click on the apple for sw updates , it tells that " there is no SW update necessary"..!

What version of Mac do you have?

The software update utility will not go the next major release it will do 10.4.1 tto 10.4.11 but will not go to 10.5 those yo have to buy.